config SND_XYZ
tristate "Foobar XYZ"
depends on SND
select SND_PCM
help
Say Y here to include support for Foobar XYZ soundcard.
To compile this driver as a module, choose M here: the module
will be called snd-xyz.

the line, select SND_PCM, specifies that the driver xyz supports
PCM. In addition to SND_PCM, the following components are
supported for select command:
SND_RAWMIDI, SND_TIMER, SND_HWDEP, SND_MPU401_UART,
SND_OPL3_LIB, SND_OPL4_LIB, SND_VX_LIB, SND_AC97_CODEC.
Add the select command for each supported component.

Note that some selections imply the lowlevel selections.
For example, PCM includes TIMER, MPU401_UART includes RAWMIDI,
AC97_CODEC includes PCM, and OPL3_LIB includes HWDEP.
You don't need to give the lowlevel selections again.

For the details of Kconfig script, refer to the kbuild
documentation.

Run cvscompile script to re-generate the configure script and
build the whole stuff again.